The document summarizes the historical progression of atomic theory from Democritus' idea of atoms in 400 BC to the modern atomic model. It explains Dalton's atomic theory in 1808 that elements are made of unique atoms that cannot be divided. In 1911, Rutherford discovered the nuclear model through alpha ray scattering experiments. Bohr then incorporated electron orbitals into his 1913 atomic model. The modern atomic model consists of a nucleus of protons and neutrons with electrons in distinct energy levels or orbitals surrounding the nucleus. It also outlines the charge, mass, and location of protons, neutrons, electrons, and the s, p, d, and f orbitals in the modern atomic model.